Any lingering euphoria felt by Celtic after their 5-1 destruction of Rangers can be banished by the invocation of the challenge they face in the Nou Camp this evening.

"The best forward line in the world," is how Brendan Rodgers described the Barcelona attack of Lionel Messi, Luis Suarez and Neymar, as his squad prepared to embark upon a Champions League group stage campaign in which they will also face Manchester City and Borussia Monchengladbach.

"This is arguably the best team in the world with a front three which is maybe the best of all time," said Rodgers.

Suarez, of course, was his cherished prodigy at Anfield and recently established a mutual admiration society by declaring Rodgers to be the best coach with whom he had worked.

Difficult

"I know that Luis used to occupy a complete back four on his own, so if you add Messi and Neymar to him, it's a very difficult task," Rodgers said.

Although Hoops fans venerate the memory of their team's 2-1 victory over Barca at Celtic Park in 2012, in a group-stage campaign in which they lost in the Catalan capital to an injury-time a goal, they are also aware of darker scenarios, such as the 6-1 drubbing in the Nou Camp on December 11, 2013, when Neymar added a hat-trick to goals by Gerard Pique, Pedro and Cristian Tello.

It was a beating which equalled Celtic's worst performance in Europe and condemned Neil Lennon's side to finish the group with their lowest-ever total of three points.

The La Liga champions also defeated Rodgers' side 3-1 in Dublin during the summer at the International Champions Cup.

Barca are not invulnerable, of course, as Alaves demonstrated by winning at the Nou Camp at the weekend, although the downside of that is that Luis Enrique's side now have extra motivation to generate a flying start to a section regarded as the toughest in the tournament.

"There is always going to be apprehension," said Rodgers, who singled out his left-back as an example of the gulf in experience, never mind resources, between the sides.

"Kieran Tierney is 19 years of age, so it's only natural that he should be apprehensive. Coming from Motherwell and then into the Nou Camp - he can't believe it.

"And after the biggest result of his life against Rangers last weekend, he now finds himself up against Messi. We're human beings here and I'm not a brain surgeon! But win, lose or draw, when we get back we'll be a better team. The more exposure you have to this sort of game, the better you become."

Asked what advice he could impart to his players, Rodgers again referred to Suarez. "I know his tricks, I know his moves but I can't play the game for the player," he said. "You can give as much insight as you can, hope that you get a little luck, stay calm when you have to and really, really enjoy the occasion.

"I'm not a coach who stands for an hour glorifying the other team. I'm a coach who focuses on us and what we do, but I do tell them about little movements Messi will make and that Luis will take you for a walk and spin in behind and he'll bump you and he'll nutmeg you."

To add to the foreboding for Celtic, Barca lost at the weekend with a weakened team, as Enrique attempted to rotate his squad and omitted Messi, Suarez and his captain Andres Iniesta.

"We were not happy of course," said Enrique of their rare home defeat.

"No one likes to lose, especially at home. We got back into the game but we lost. I hope it has no effect on the squad, we will have to see.

Improve

"We have had two days of rest. We are looking forward to tomorrow and we will see what happens. After every game, whether it is a win or a loss, there are things to improve.

"Our objective is to win the next game, it is the only one we can think about. We don't want to think about the long run, the key thing is to beat Celtic.

"We need to play good football because it will not be easy."

Rodgers will have to do without his top scorer Leigh Griffiths but he has Moussa Dembele, who netted the first hat-trick in an Old Firm game for more than 50 years.

"He will handle it like he did at the weekend," said the manager. "There's a misconception about Moussa, that I brought him to be a second-choice striker. He will show that he will be a big player for Celtic over the years."